At present, in the process for manufacturing a TFT-LCD, a glass substrate includes a plurality of LCD Q-Panels, wherein each Q-Panel comprises a plurality of LCD panels and has one or two sets of general signal connection port(s). The lengths of signal transmission lines between each LCD panel and the general signal connection port are different since the distances therebetween are different. During an actual manufacturing, all the signal transmission lines are made very thin to improve the utilization of the glass substrate; and since the Q-Panel is relatively large, the signal transmission lines between the LCD panel which is far away from the general signal connection port among the Q-Panel and the general signal connection port are relatively longer, and thus the resistances of these signal transmission lines are larger. When the same signals are loaded onto the general signal connection port of the Q-Panel, the paths along which the loaded signals are transferred to the individual LCD panels are shown in FIG. 1. As the distance between the LCD panel 12 and the general signal connection port 11 varies from one to another, the resistance of the signal transmission line 13 therebetween varies. FIG. 2 shows a schematic diagram of an equivalent resistance thereof, wherein R1 represents a resistance of the signal transmission line between the general signal connection port 11 and the LCD panel V1, R2 represents a resistance of that between the LCD panel V1 and the LCD panel V2, R3 represents a resistance of that between the LCD panel V2 and the LCD panel V3, . . . Rn represents a resistance of that between the LCD panel Vn−1 and the LCD panel Vn, and so on.
In test, a testing signal is loaded into the general signal connection port of the Q-Panel, the resistance of the signal transmission line between the LCD panel and the general signal connection port gradually increases as the distance therebetween increases, and thus the voltage drop caused by the resistance increases continuously. Therefore, the farther the LCD panel is from the general signal connection port, the less the strength of the testing signal received by the LCD panel is, and thus the less the luminance of the LCD panel after being lighted up is, and in a certain situation, it can not even be lighted up, which affects the test seriously.
In summary, the resistance of the signal transmission line and the voltage drop caused by the resistance are relatively large when the length of the signal transmission line is long since the Q-Panel is large and the signal transmission line is thin, and thus it causes a large attenuation of the signal over the resistance of the signal transmission line when the signal is loaded into the general signal connection port.